Wallabies winger Drew Mitchell is "not happy" at being axed but that's just how no-nonsense New South Wales Waratahs coach Michael Cheika wants it after ringing the changes for the Super Rugby clash with the Cheetahs on Friday night.

Cheika made six personnel and two positional changes from the side thrashed 35-6 by the Brumbies on Saturday, with Mitchell and Test prop Sekope Kepu the highest-profile casualties.

Mitchell and Kepu were both omitted from the match-day 22 altogether, with Cheika saying there was no room for under-performing stars as the Waratahs sought to avoid a third loss from four starts this campaign.

"I want guys to fulfil their potential," Cheika told AAP. "Maybe I judge those guys at a higher standard. I don't think they've been playing poorly, but I think they've got more potential to achieve and I really want guys to play to the best of their ability at their own level. That's very important to me."

Cheika said he had a two-part "private conversation" with Mitchell before and after axing the 60-Test winger to explain exactly where the 28-year-old needed to improve.

"He's not happy, obviously. But I want them to be not happy. I want them to care about playing," Cheika said.

The first-year Super Rugby coach said Kepu was in the same boat.

"I know he's playing for Australia and all that, but he can be so much better," Cheika said. "We need to be getting the guys who are playing for Australia to be of the quality of being picked in the World XV."

Lachie Turner and Peter Betham have been promoted to form a new starting wing combination and marquee signing Israel Folau reverts to fullback. Wallabies utility Berrick Barnes makes his first appearance of the season, returning from a knee injury at inside centre.